def putchar(self, addr, data):
"""
Concrete/Symbolic putchar implementation
@param addr: the address to put a concrete or symbolic content
@param data: the content to put in C{addr}
@todo: if addr is Readable/Executable? Double checked when accesing parebnt class!!!
"""
if issymbolic(addr):
logger.debug("Write to symbolic address %s", addr)
addr_min, addr_max = self.solver.minmax(addr)
logger.debug("Range: %x <-> %x", addr_min, addr_max)
#Mark and intialize symbolic range
for i in xrange(addr_min, addr_max+1):
if not self.isWriteable(i):
raise MemoryException("No Access Writting", i)
for i in xrange(addr_min, addr_max+1):
if not i in self.addr2symbol:
self.symbol[i] = self.getchar(i)
self.addr2symbol.add(i)
self.symbol[addr] = data
else:
#concrete addr case
if not self.isWriteable(addr):
raise MemoryException("No Access Writting", addr)
if issymbolic(data):
self.symbol[addr] = data
self.addr2symbol.add(addr)
else:
#both concrete
self.addr2symbol.discard(addr)
super(SMemory, self).putchar(addr, data)
def test_one_concrete_one_symbolic(self):
#global mainsolver
my_solver = Solver()
mem = SMemory(my_solver, 32, 12)
addr_for_symbol1 = mem.mmap(None, 0x1000, 'rwx')
mem.putchar(addr_for_symbol1, 'A')
symbol1 = my_solver.mkBitVec(8)
my_solver.add(OR(symbol1==ord('B'), symbol1==ord('C')))
mem.putchar(addr_for_symbol1+1, symbol1)
values = list(my_solver.getallvalues(symbol1))
self.assertIn(ord('B'), values)
self.assertIn(ord('C'), values)
symbol2 = my_solver.mkBitVec(32)
my_solver.add(symbol2>=addr_for_symbol1)
my_solver.add(symbol2<=addr_for_symbol1+1)
c = mem.getchar(symbol2)
self.assertTrue(issymbolic(c))
values = list(my_solver.getallvalues(c))
self.assertIn(ord('A'), values)
self.assertIn(ord('B'), values)
self.assertIn(ord('C'), values)
def getchar(self, addr):
"""
Concrete/Symbolic getchar implementation
@rtype: str[1] or BitVec[8]
@param addr: the address to obtain its content
@return: a character or a symbol stored in C{addr}
@todo: if addr is Readable/Executable? Double checked when accesing parebnt class!!!
"""
if issymbolic(addr):
logger.debug("Read from symbolic address %s", str(addr).replace("\n",""))
addr_min, addr_max = self.solver.minmax(addr)
self.solver.add(addr.uge(addr_min))
self.solver.add(addr.ule(addr_max))
logger.debug("Range: %x <-> %x", addr_min, addr_max)
#Symbolic address case
for i in xrange(addr_min, addr_max+1):
if not self.isReadable(i):
raise MemoryException("No Access Reading", i)
if not i in self.addr2symbol:
self.symbol[i] = self.getchar(i)
self.addr2symbol.add(i)
return self.solver.simplify(self.symbol[addr])
if not self.isReadable(addr):
raise MemoryException("No Access Reading", addr)
#if the pointed value is a symbol...
if self.isSymbolic(addr):
return self.solver.simplify(self.symbol[addr])
return super(SMemory, self).getchar(addr)
def test_mix_of_concrete_and_symbolic(self):
my_solver = Solver()
mem = SMemory(my_solver, 32, 12)
start_mapping_addr = mem.mmap(None, 0x1000, 'rwx')
concretes = [0, 2, 4, 6]
symbolics = [1, 3, 5, 7]
for range in concretes:
mem.putchar(start_mapping_addr+range, 'C')
for range in symbolics:
mem.putchar(start_mapping_addr+range, my_solver.mkBitVec(8))
for range in concretes:
self.assertTrue(isconcrete(mem.getchar(start_mapping_addr+range)))
for range in concretes:
self.assertFalse(issymbolic(mem.getchar(start_mapping_addr+range)))
for range in symbolics:
self.assertTrue(issymbolic(mem.getchar(start_mapping_addr+range)))
for range in symbolics:
self.assertFalse(isconcrete(mem.getchar(start_mapping_addr+range)))
for range in symbolics:
mem.putchar(start_mapping_addr+range, 'C')
for range in concretes:
mem.putchar(start_mapping_addr+range, my_solver.mkBitVec(8))
for range in symbolics:
self.assertTrue(isconcrete(mem.getchar(start_mapping_addr+range)))
for range in symbolics:
self.assertFalse(issymbolic(mem.getchar(start_mapping_addr+range)))
for range in concretes:
self.assertTrue(issymbolic(mem.getchar(start_mapping_addr+range)))
for range in concretes:
self.assertFalse(isconcrete(mem.getchar(start_mapping_addr+range)))
def testBasicSymbolic(self):
my_solver = Solver()
mem = SMemory(my_solver, 32, 12)
#alloc/map a little mem
size = 0x10000
addr = mem.mmap(None, size, 'rwx')
#initialize first 10 bytes as [100, 101, 102, .. 109]
for i in xrange(addr, addr+10):
mem.putchar(i, chr(100+i-addr))
#mak a free symbol of 32 bits
x = my_solver.mkBitVec(32)
#constraint it to range into [addr, addr+10)
my_solver.add(x>=addr)
my_solver.add(x<addr+10)
#Well.. x is symbolic
self.assertTrue(issymbolic(x))
#It shall be a solution
self.assertTrue(my_solver.check(), 'sat')
#if we ask for a possible solution (an x that comply with the constraints)
sol = my_solver.getvalue(x)
#it should comply..
self.assertTrue(sol >= addr and sol<addr+10)
#min and max value should be addr and addr+9
m, M = my_solver.minmax(x)
self.assertEqual(m, addr)
self.assertEqual(M, addr+9)
#If we ask for all possible solutions...
for val in my_solver.getallvalues(x):
#any solution must comply..
self.assertTrue(sol >= addr and sol<addr+10)
#so now lets ask the memory for values pointed by addr
c = mem.getchar(x)
for val in my_solver.getallvalues(c):
self.assertTrue(val>=100 and val<110)
#constarint the address a litlle more
my_solver.add(x<=addr)
#It shall be a solution
self.assertTrue(my_solver.check(), 'sat')
#if we ask for a possible solution
sol = my_solver.getvalue(x)
#it must be addr
self.assertTrue(sol == addr)
#lets ask the memory for the value under that address
c = mem.getchar(x)
sol = my_solver.getvalue(c)
self.assertTrue(sol==100)
raise NotImplemented
file(folder+os.sep+'test_%d.txt'%test_case_no,'a').write("%s: %s\n"%(symbol.name, repr(buf)))
print "starting"
try:
while len(states) !=0:
#select a suitable state to analize
current_state = get_state()
try:
#load the state
linux = pickle.load(file(folder+os.sep+current_state,'r'))
#execute until exception or finnish
while linux.execute():
linux.cpu.PC = linux.solver.simplify(linux.cpu.PC)
#if PC gets "tainted" with symbols do stuff
if issymbolic(linux.cpu.PC):
#get all possible PC destinations (raise if more tahn 100 options)
vals = list(linux.solver.getallvalues(linux.cpu.PC, maxcnt = 100))
print "Symbolic PC found, possible detinations are: ", ["%x"%x for x in vals]
#Shuffle the possibilities,
random.shuffle(vals)
#we will keep one state for the current analisys and save
#all the rest to files
current_pc = linux.cpu.PC
for new_pc in vals[1:]:
name = 'dump_%016x_%d.pkl'%(new_pc, linux.cpu.icount)
print "\tSaving state %s PC: 0x%x"%(name, new_pc)
linux.solver.push()
#add the constraint
linux.solver.add(current_pc == new_pc)
#and set the PC to the concretye destination
